Farmers are still exposing themselves to serious risks when mixing slurry – with less than a fifth obeying the key rule to escape deadly gases.

The Health and Safety Executive says just 18% of them they spoke to waited the recommended 30 minutes before going back into a building where the potentially lethal material is being mixed.

The news comes in the wake of an ongoing campaign to highlight the dangers involved and a little over a year since Ulster Rugby player Nevin Spence, his brother Graham and father Noel were killed in a slurry tank accident at the family farm near Hillsborough, Co Down.

The HSENI survey also found 14% of farmers they spoke to waited only five minutes, or even less, after the start of mixing before re-entering the building.

The health and safety body said the “figures are all the more shocking considering that all the farmers who participated in the survey confirmed that they were well aware of the risks from slurry gas during the mixing process”.

They added 20% reported either they or a family member had been affected one or more times by the most deadly gas produced by slurry – hydrogen sulphide.

Health and Safety Executive chief Keith Morrison said it is “demoralising that many farmers are still willing to risk their lives when mixing slurry”.

He added: “Farmers should follow all of the recommended safety advice, and at the very least they need to stay out of the mixing building for at least half an hour.

“Just one breath of slurry gas can cause serious injury or even death.”

Ulster Farmers’ Union president Ian Marshall added the dangers of slurry gas are “very well-known and it’s hard to think of any excuse which would justify taking the risk”.

He said: “One death on a farm is one too many and farmers need to take responsibility for their own safety by following the advice that’s being given.”

Agriculture Minister Michelle O’Neill warned farmers to stay safe describing the gases given off as “lethal”.

She added: “Just one breath of slurry gas can cause serious injury or even death.”